Ch 7 study guide: Control of Microbial Growth Flashcards
What does Sepsis refer to?
refers to bacterial
contamination (ex. septic tank)
What is Asepsis?
is the absence of
significant contamination
What is Sterilization?
removing and destroying
all microbial life
What is Commercial sterilization
killing
Clostridium botulinum endospores from
canned goods
What is Disinfection?
destroying harmful
microorganisms on a surface
What is Antisepsis?
destroying harmful
microorganisms from living tissue
How is sterilization distinct from the rest?
it removes and destroys ALL microbial life
Degerming
the mechanical removal of microbes from a limited area ex: alchohol swab
What is Sanitization?
lowering microbial counts on eating utensils to safe levels ex: dishwasher
whats a Biocide (germicide)?
treatments that kill microbes
- Fungicide: kills fungi
- Virucide: inactivates viruses
Bacteriostasis means..
inhibit growth and multiplication of microbes
What is particular about antisepsis?
It destroys harmful microorganisms from living tissue
Understand the shape of the microbial death curve.
More time that is exposed, more death occurs
What are the four factors that affect the control of the microbial death rate?
- Number of microbes
- Environmental influences
- Time of exposure
- characteristics of microbe
Which microorganism is the most resistant?
Prions
Which microorganism is the least resistant?
Viruses with lipid envelopes
does the presence of organic material affect most antimicrobial treatments?
The presence of organic matter often INHIBITS the action of chemical ANTImicrobials
What is the difference between dry heat and moist heat?
- Dry heat kills by oxidation effects (ex: direct flame)
- Moist heat coagulates/denatures proteins (ex: steam, autoclave, boiling, pasteurization)
Which type of heat is more effective at killing microorganisms? Why?
moist heat
it kills all organisms and endospores by denaturing their enzymes?
What are some examples of dry heat?
- Direct flaming
-Hot air sterilization (Oven)